gtkmm24 has been replaced by gtkmm2
glibmm24 has been replaced by glibmm2
gtkmm24-devel has been replaced by gtkmm2-devel
glibmm24-devel has been replaced by glibmm2-devel

All the new packages are providing the old package name (with version, which is
good). But they are not obsoleting it.

Without the "Obsoletes:" tag, the package manager does not have a hint that
gtkmm2 is actually a newer version of gtkmm24 and that gtkmm24 should be
uninstalled when a gtkmm2 package is available.

But in this particular case, that would be the right thing to do because:

- gtkmm2 is binary compatible with the libraries from gtkmm24
- gtkmm2 and gtkmm24 are not parallel installable, they contain overlapping
files
- gtkmm24 is orphaned, there will never be a new package with this package name

The tags which should be added are:

gtkmm2
Obsoletes: gtkmm24 <= 2.10.1

gtkmm2-devel
Obsoletes: gtkmm24-devel <= 2.10.1

glibmm2
Obsoletes: glibmm24 <= 2.12.0

glibmm2-devel
Obsoletes: glibmm24-devel <= 2.12.0

The versions should be written out (i.e. "<= 2.10.1", not "<= %{version}")
because 2.10.1 is the last version that had been packaged under the old gtkmm24
package name.